| Names | |
|---|---|
| Other names μ-Telluride(ditelluroxo)dialuminium, Dialuminium tritelluride, Aluminium (III) telluride | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider |
|
| ECHA InfoCard | 100.031.751 |
| EC Number |
|
| |
| |
| Properties | |
| Al2Te3 | |
| Molar mass | 436.76 g/mol |
| Appearance | dark grey to black solid[1] |
| Density | 4.5 g/cm3[1] |
| Melting point | 895[2] °C (1,643 °F; 1,168 K) |
| decomposes | |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Aluminium telluride is aninorganicchemical compound ofaluminium andtellurium with thechemical formula Al2Te3.
Aluminium telluride can be obtained by direct combination of aluminium metal with elemental tellurium at 1,000 °C (1,270 K; 1,830 °F).[1]
Aluminium telluride is a very air-sensitive[3] dark grey to black solid.[1] It has aband gap of 2.4 eV.[4] The compound decomposes in humid air.[5]
In its pure form, it occurs in at least twophases. The orange-red low-temperature (α) modification transforms into the yellow high-temperature (β) form at 720 °C (993 K; 1,328 °F). The conversion from β- to α-Al2Te3, which is associated with such a smallenthalpy change that it cannot be observed withdifferential thermal analysis, takes place after prolongedannealing just below the conversion point. The α form crystallizes in themonoclinic crystal system with thelattice constants a = 13.885Å, b = 7.189 Å, c = 4.246 Å, p = 90.21° and an additionalsuperstructure. The β form has amonoclinic crystal structure withspace groupP21/c and the lattice constants a = 7.181(1) Å, b = 12.848(3) Å, c = 14.167(3) Å, and b= 90.04(2)°. This form represents a separate structure type. The tellurium atoms form ahexagonal dense packing parallel to the(001) plane; one-third of the tetrahedral vacancies are occupied by aluminium atoms, whereby the tetrahedral vacancies are occupied in such a way that a layered structure is formed. Some sources also report another form of the defectwurtzite type.[3]
Aluminium telluride is used in thesemiconductor industry.[1] It can also be used to producehydrogen telluride by reacting withhydrogen chloride.[6]
